


The Night We Won't Forget

by Dimension_K166



Category: Adventure Time
Genre: Angst, Awkward First Times, Awkward Romance, Everything else is consensual, Fern's damn curious, Foreplay, Hand Jobs, Kink Exploration, M/M, Plot What Plot/Porn Without Plot, Porn With Plot, Porn with Feelings, Sexual Tension, Somnophilia, and Finn loves it, its non-con cause of the sleep kinkiness, sexploration
Language: English
Status: In-Progress
Published: 2018-12-14
Updated: 2018-12-26
Packaged: 2019-09-18 09:13:13
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 2
Words: 3,166
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16992198
Author URL: https://archiveofourown.org/users/Dimension_K166/pseuds/Dimension_K166
Summary: Fern's spent too much time thinking on top of the tree house, and now he's gunna explore it's inhabitants during the night.





	1. The Night that Started it All

**Author's Note:**

> Hey guys! It's been 4 years since I've written something so please bear with me on this one! I do hope you enjoy this clusterfuck of a fic, and please don't hesitate if there's a grammar error you wanna point out! Thank you for reading! <3

The moon’s light beamed down through the trees that outlined the grasslands, the forest was as if a sea of rattling leaves that fought against the rustling of grass while out on the hilltop stood the almighty galleon: a treehouse within a lone Willow tree. Upon it’s top laid a creature, spread eagle against the leaves he couldn’t even feel the chill of the night’s cold breeze. Insomnia wrapped around his mind, his eyes were set on the falling star-lit skies.   
  
It’s been like this for about a week for Fern, nose up at the stars while mind in chaos. He then turns over onto his side, knees pressing up against his chest as he closed his eyes. For a moment he could feel something, his mind painting pictures with it’s brush of subconsciousness. He knew the mind could play tricks and he wanted to at least give in for once.   
  
Suffocated in fantasy, he could feel as if his own body was warm like  _ his _ . All snuggled up tightly in  _ his _ sleeping bag, feeling  _ his _ nose bitten by the cold, feeling  _ his _ chest rise and fall, feeling  _ his _ heartbeat. Fern’s hand automatically gripped the stalks of the Willow tree, biting his lip and shutting his eyes tighter. 

 

**_This feeling isn’t even my own! This feeling is fictitious! This feeling is the dream and this life is the nightmare!_ **

 

Tears of sap forms at the corners, rolling down his cheeks as he lifted himself up. Raising his forearm, he uses it as if an amateur removing makeup with a towel.    
  
Fern let his arm fall to his side, staring down at the dark landscape blankly. Everything felt so foreign to him that he commonly found himself questioning if he’s on the physical plane or in a mere fantasy. And for that he hated it. The other hand slowly crawled over the sap-soaked forearm, rubbing the substance into the grass blades to dilute it.    
  
****

**_Why is this my destiny? Is this my fate? Do I deserve this? What am I? Who am I? I’m Finn, but I’m... Fern?_ **

 

Since the day he was formed, Fern asked those same questions out to every night sky in hopes of a reply. But so far the only ones he’s gotten were the sounds of crickets within the land and the soothing, soft Fall gusts. His digits curled into fists, the frustration finally getting to him as he jumped to his feet. Carelessly, he stomped to and fro in deep thought while murmuring to himself. 

  
“...I don’t deserve this.....I know who I am..... I don’t need  _ him _ to tell me what’s right from wrong..... I’m the  _ hero _ . He’s the  _ fraud _ .”   


  
**_He took my home. He took my bathroom. He took my Jake._ **

 

And with the fire that burned inside of him, Fern instinctively scaled down the stalks to climb through the open bathroom window. His soft grass feet never made a sound as he took one step up to the master bedroom. And once up to the top step his eyes locked onto the boy’s bed. Fern took a respite to take in what he was seeing, he’s never been in here since he formed. It felt like only yesterday Fern slept all squirreled away in that sleeping bag.    
  
The grassy creature shut his eyes for a moment to only open them, revealing menacing, glowing eyes with slitted pupils. He started approaching the bed, claws out and eyes dragging up Finn’s body to the human boy’s face sleeping peacefully and sound. Fern felt himself freeze up, his claws slowly retracting back into his grass body while he fixed his gaze on the way Finn’s lips softly opened and closed with every soft breath. He couldn’t really explain why that was his infatuation of choice, he even pondered himself if all the rage in the world can make him do the unthinkable: take the life of another.   
  
In defeat he sat at the foot of the bed, face in the palms of his hands while his fingers massaged his forehead and cheeks. Within his grassy mind Fern felt something he was trying to suppress all this time, the teenage curiosity was getting to him and in the wake of that realization he turned his head away.    


  
**_This is stupid. As much as I hate it.....he’s me..... And that means..... the same desires..... This is so wrong._ **   


  
His cheeks grew into a different green hue as he gripped the furs that draped over the bed. With a soft snort, he was in disbelief of his own urges and contemplating either to  fight them or to give into them. Fern’s eyes glanced back at the boy, but this time lingering as if to outline something carefully. He watched as Finn’s chest rose and fell, every flutter of eyelids, every movement he made. And for some reason Fern couldn’t pull his interest away. The creature’s knees met the bed softly as his claws gripped the furs, crawling toward the sleeping boy. He hung above Finn, curiosity fueled his actions as fingertips shyly slipped between the opening of the bag.  **_So warm._ ** His gaze burned holes into the boy as Fern’s whole hand cautiously slid in, shyly pressing against the boy’s clothed chest. Fern bit his lower lip, feeling Finn’s heartbeat did something to him that he couldn’t comprehend, leading into a new form of sexual awakening.  **_I want more._ **

His hand gently slid out to start undoing the bag slowly, one loop at a time. He was too perplexed by the boy’s breathing patterns to listen to the logical side of his mind telling him to stop. It was as if he wanted this more than his own morals would allow it, or was he himself fueled by the teenager within him? Once fully undone, Fern peeled the bag back to reveal the boy’s red onesie. Oh he missed the feeling of it against his own skin. His fingertips then pressed lightly against the fabric that wrapped around Finn’s lower chest, and another grassy hand hovered lower. All of this was just so new to the Fern, but yet felt so familiar. He knew exactly where Finn, or his own, sensitive, tickle spots were located and using this knowledge let him advance his attack. It was as if going into a dungeon with a fully written map, every doorway and secret drawn out, he knew exactly how to play this game perfectly.

Soon enough his hands waltzed all the way down to the boy’s lower stomach and that’s when the creature noticed something he didn't before this point of no return. Finn was half-chubbed and Fern guessed it was his own handy work. With his eyes wide and overture halted, he stumbled over the concept of him being the cause of this.

  
**_Am I good at this? Is he gunna wake up? Please don’t!_ ** **_  
_ **

  
His eyes darted up to Finn’s face in a panic, noticing the boy had somewhat of a smirk but was still in deep slumber. He sighed relieved as his focus went back onto his own hand against the red fabric of the onesie, he’s really gotta watch it this time. He spent some good time staring down at Finn’s.....his cock? He knew exactly where to touch, where to not, and that chased around his mind like a cat chasing a laser. He wanted to touch it badly, and he had to use all his strength to hold himself back. Something within bellowed deeply inside Fern as if Finn himself was begging into his ear, how could Fern not give in?

Looking over his shoulder he glanced at Jake, the animal was fast asleep in the opposite side of the room. From his own memories, Fern knew nothing could wake that rock up. Turning his head back Fern’s focus was glued on the boy, he carefully extended a hand upon the wool that separated both of them from touch. Now this was the warmest part of Finn that the creature has yet to feel, all rational thought leaped outta the window as instinct kicked in. He started softly palming him down, occasionally glancing up at Finn at each tiny sound the boy made, and of course glancing back at Jake if Finn made a noise Fern deemed “too loud”.  **_So far so good._ **

Fern’s curiosity got the best of him as he started trying to grip his cock though the fabric but to no avail. He hesitates to think of some sort of solution, but ends up trying something risky. Fern climbs back onto Finn like the first time he touched the boy, making sure his movements were slow and careful, not applying pressure against the furs too fast with his knees. In a standstill, the creature took this time to analyze the boy’s face: The drops of sweat that stood out above Finn’s brow, the different pattern to his breathing since the first time Fern stepped in, and the way Finn’s legs spread apart waiting for more. He was in REM, not fully awake but to the point the boy could comprehend what was going on. The thought of that only made Fern want him more.

The creature’s hand glided up the boy’s body, this time not avoiding any sensitive spots as his fingertips found their resting place at the hem of Finn’s hat. That entire duration was such bliss to Fern, watching Finn squirm and whimper yearningly at such touch. He missed the feeling done to himself. The creature’s lips parted to reveal semi-sharp teeth as he slowly pulled the boy’s hat up a few inches, leaning in to run his teeth lightly against the exposed skin. This caused Finn’s hands to immediately grip Fern’s upper back, the boy was finally coming to consciousness.   
  


“Shhh.....”, Fern cooed into his ear softly, “ _...or he’ll hear you... _ ”


	2. A Surprising Discovery

**Summary for the Chapter:**

> Fern relives the night he spends with Finn.

**Notes for the Chapter:**

> Aw jeez! I'm sorry this took awhile to write, I really wanted to give it my all after all the love I got. Thank you for being so patient and Happy Holidays! <3

Time flew by and the rustling of grass and leaves ceased to a whisper as the Fall breeze blew its final song. Over the rolling hills in the distance the Sun peeked over the hill tops to light up the darkened landscape, the lone Willow Treehouse standing proud against it’s rays. Upon the top of the Willow Tree laid a creature hidden in its leaves, nose up watching the sky turn from indigo, to pink, to blue. It’s been days since he last climbed down to enter the abode, too awkward to confront the boy who lived within.   
  
Fern sighs softly, laying his forearm against his eyes to shield them from the bright sky. His cheeks grew full of color as he recalled that night days ago. He couldn’t get Finn’s look outta his mind, the way the boy’s eyes widened full of wonder, the way his lips parted to exhale a gasp...

 

~~~~~

 

Fern’s fingers tangled in Finn’s hair as the boy went to work. Both of them gave up on keeping quiet, their own hormones leading the dance to something more scandalous and risky. Fern bit down on his own lip as Finn’s teeth sank into his neck, and in the heat of the moment the creature ground against the boy’s lap. That warranted a hot breath against Fern’s neck, causing a shiver up his spine.  **_So experienced~_ **   
  
Only mere minutes ago Fern had his finger wrapped around Finn, making the boy beg for him while marking up the flesh of his neck. But by now Fern was the one doing the begging. Perched in the boy’s lap, he ground against Finn’s concealed cock. Causing the boy to tense up, his grip on Fern’s hips tightening in reflex. And oh how Fern loved it, how he just wanted more.

  
Finn gasps next to Fern’s ear, the pressure against his cock driving him mad as he throbbed excitedly, quivering a moan, “Aw fuck Fern-“

 

The creature’s grin twisted into a smirk and eyes peered down into the boy’s, pressing harder against the boy’s cock to the point he could feel a heartbeat. Finn melted like butter exposed to the sun, causing him to grip Fern’s ass tightly. He wanted to just do something, anything, and with a frustrated grunt Finn pulls away to start stripping himself of his onesie. Fern slipped off of him, back into the bed to mirror what Finn was doing. Gripping the sides of his pants to slide them off he was then in hesitation. Something felt off and Fern couldn’t put his finger on it. 

  
Every since he got this grass bod, the way he would “feel” things has always been off. He spent one sitting trying to injure himself to test the feeling of pain to no avail, but it never meant he couldn’t feel some kind of sensation. Having anything brush up against him gave him a numbed down version of pins and needles, like some kind of distorted hot breath that would leave goosebumps in its wake. But tonight was different, something new besides numbed pain and a soft, loving stoke against his shoulder. The feeling between his legs was so foreign to how it felt when he had a bod of flesh and blood, it was as if too sensitive to the touch.  **_Feeling warm and... wet?_ **   
  
Fern jumped back to reality, eyes widened as he panicky peered down into his pants. Outta shock he pulled them up as fast as possible, looking back up at a very much confused Finn.   


  
“Anything wrong?”, Finn whispered, his cock sprung up while he pulled his onesie down to his knees.   


  
Fern stared down the boy like a deer caught in high beams. The boy’s brows furrowed, sitting on the bed by the creature to put his hand on the other’s shoulder. Fern jolted softly in response while his claws dug into his own lap.   


  
“Uh- I....Finn I- I have no idea how to explain this-“, Fern stumbled with his words, clawing digging deeper, “I- I th- think I should just go- this is weird- I’m weird- I’m sorr-“   


  
“What, no- chill man, it’s all gunna be ok. I’m glad you came to visit me, I always worry about you when you’re... you know, up there...”   


  
Fern looks at him dead in the eye, retracting his claws from his thighs, and promptly putting them on both of the boy’s shoulders, “Finn. It’s not you, its me. I can’t explain this. I have to go.”   
  
Silence fell throughout the room as the boy pondered for a second, breaking the staring contest by looking down as his own partially naked bod. Maybe this was going too fast?   


  
“...If you can’t tell me... Can you show me what’s wrong?”   


  
Fern’s cheeks lit up like late night neon as he trembled indecisively, he didn’t really know what to say or do. One part of him wants to continue but the other wants to run, “Uh- uhhhh- uuhm... Finn I don’t know... maybe next time? I seriously have no idea- what to even... You know what, I want your take on this. Maybe you’ve had experience or- ok I’m just gunna shut up and do this-“   
  
Fern gripped the hem of his pants tightly, pulling them down shakily slow to expose an unexplored part of himself that he still wasn’t sure to show to the other. It took the boy a second to realize what he was looking at, but in the realization of what it was Finn’s eyes widened in intriguing curiosity. Jaw dropping as he let out a hot stutter, “I- Is- is that- a... pussy?”

 

~~~~~

 

Fern jumps at the sound of the bathroom window opening, his gaze quickly turning to the noise of shoes scrambling up the branches and stalks of the Willow tree.

 

  
“Fern? May I come up?”, Finn peeked over the leaves shyly.   


  
With a frog in his throat the creature nodded, patting the stalks next to him. He couldn’t just say no to Finn, that would be unethical. Plus Fern didn’t want to make things worse than they already were.   
  
Finn smiles warmly and climbs up, standing on stable branches while walking over cautiously, “Thanks... I was just wondering how you’re doing, yesterday’s greeting felt a bit off.....”   
  
Finn trailed off as he sat next to Fern, keeping a bit of distance to not shake the creature up. Finn’s noticed things haven't been the same since that night, and he’s somewhat disturbed by it. His brain’s been at this for the days following, he wants their trust to climb, feelings to be felt, Fern to like him...   
  
Finn blushes and looks away off into the horizon of rolling hills, “... I really wanna talk...Fern.”   


  
“Is it about me?”   


  
“Well kinda-“   


  
Fern sighs heavily, “Look, that was just a one time thing- I just... I need space ok. I need to figure this out by myself, I can’t believe it took me months to finally you know- realize- but then again plant boys don’t use the bathroom right Finn?”   
  
Finn was silent, looking back into Fern’s eyes, “... If this how you feel, it’s ok. I just don’t want you to feel alone on this. You’re me in a way and I gotta help myself right? I’m always here when you need me,” the boy leans in to kiss Fern’s cheek shyly before getting back onto his feet to take his leave. He felt a slight tug at his shirt that stopped him dead in his tracks.   


  
“Stay... please,” Fern murmured.   


  
Finn smiles, turning around to sit back next to the creature but this time only closer, “So... you wanna go first?”   
  
Fern pauses to find words, “I... since then I have been thinking. Imagining. Fantasizing... I feel so... gross. Like this seems like a bad dream gone good, I feel like I've always wondered what it’s like to... have one. And now that I do- I- what to do with it?!”   
  
Finn nods, “Yeah, I know I’ve once had a dream where I had one-“   


  
“I know, that was pre-sword. I had it, too.“   


  
Finn chuckles, blushing and looking out at the hills, “Yeah.....”, he bites his lip as there was silence for a brief moment, “You... you said you need help?”   


  
“What?”   


  
“You said that you- you didn't know what to...do with it- and I was just wondering if... we can maybe... experiment sometime? Like only focus on you! Not myself at all! It’ll be an “only you” night. Promise.”   
  
Fern stumbled on his choices, fumbling and knitting his fingers together, “Hmm- I’ll... take your offer into consideration. You are the only one I really... Yeah, sometime later? I’ll let you know, promise.”   
  
Finn smiles and scoots closer to the creature, leaning his head against Fern’s shoulder while softly blanketing his hand over his grassy one, “I’m glad to be like this with you, that you see me this way. I’ll be gentle, this’ll be fun. Promise.”   
  
The creature gently laid his head against the boy’s, shutting his eyes and lips curling into a warm smile, “Thanks Finn... I’m glad I have you...”


End file.
